A system in which a wireless access network and another network such as the Internet are connected to each other is conventionally used. One example of such a system is Long Term Evolution (LTE). In LTE, a wireless access network and another network are connected to each other via Evolved Packet Core (EPC), which is a core network. Further, all data is converted into packets that are based on an internet protocol (IP) and transferred. In such a system, a user who uses a wireless terminal can use an application provided by the Internet.
As a technology for improving usability when an application on the other network is used from the wireless access network in such a system, there has been proposed mobile edge computing (MEC). In MEC, a cache server that temporarily holds data associated with the application is provided within the wireless access network. Accessing the data held in this cache server can shorten time when transferring data to the wireless terminal and improve usability.
One proposed technology for the cache server is a system in which a local cache is provided to a wireless access network, and a fee is charged when a user uses data held in the local cache (see, for example, Patent Literature 1). In this system, a fee is charged when data such as content is provided from the network to the local cache.